Are you a new crocheter struggling to choose the right yarn for your project? In this ultimate guide, we will explore what WPI is, why it’s useful, and how to measure it, along with looking into yarn weights and their importance in crochet. You’ll understand the significance of WPI in yarn selection and substitution, and get tips on choosing the right yarn weight for your specific knitting or crochet project with the help of a yarn weight chart.
What Are Yarn Weights?
Yarn weights refer to the thickness of the yarn strand. They range from ultra-fine lace weight to super bulky jumbo weight. Each weight category serves different purposes and suits various types of projects. For instance, lace weight yarn is ideal for delicate, intricate pieces like doilies and lightweight shawls, while bulky yarns are perfect for chunky blankets and winter garments. Common yarn weight categories include lace, fingering, sport, DK (double knitting), worsted, aran, bulky, and super bulky.
Knowing the yarn weight that best fits your project allows you to create items with the correct gauge and drape. It also helps when selecting the appropriate tools such as the right size of crochet hook, ensuring that your project not only looks good but also feels just the way it’s supposed to.
Why Do Yarn Weights Matter in Crochet?
Yarn weights significantly impact the outcome of your crochet projects. The weight of the yarn determines the size of the crochet hook you should use, the gauge, and the overall drape and texture of the finished piece. Using the wrong yarn weight can result in a project that is too stiff or too loose, which can affect both the appearance and functionality of the item. Understanding yarn weights ensures that your projects come out as intended, fitting the right dimensions and maintaining the desired look and feel.
Each crochet pattern is typically designed with a specific yarn weight in mind, and deviating from the recommended yarn weight can lead to differences in the final product. Using a lighter yarn than recommended can make your item smaller and more delicate, which might not be suitable for its intended use. On the other hand, using a heavier yarn can result in a larger, bulkier piece that may not look as refined as you want.
Yarn weight also affects how the fabric drapes, which refers to how the fabric falls and flows. If the yarn is too thick, the project can look stiff and rigid. If the yarn is too thin, it might lack structure and form. Getting the right drape is crucial for items like shawls, scarves, and garments, where the way the fabric moves and feels is very important. Choosing the right yarn weight helps ensure your finished piece looks and functions as intended.
How to Choose the Right Yarn Weight
Choosing the right yarn weight depends on the project you’re working on. For garments and accessories, you’ll want to consider the drape and wearability of the finished item. For example, a soft, drapey yarn is perfect for a shawl, while a sturdier yarn might be better for a structured bag. Always check the pattern recommendations if you’re following one, as designers typically specify the best yarn weight for their designs. Additionally, you should consider the season – lighter weights for summer wearables and heavier weights for warm winter jumpers and blankets.
Your personal preferences also play a significant role in choosing the right yarn weight. Some crafters prefer the speed and ease of working with thicker yarns, while others enjoy the precision and detail of finer yarns. Your comfort and enjoyment in the crafting process are just as important as the technical aspects.
What is WPI (Wraps Per Inch) and Why is it Useful?
Wraps Per Inch (WPI) is a method used to measure the thickness of yarn. By wrapping the yarn around a ruler or a specialised tool and counting the number of wraps that fit into an inch, you can determine the yarn’s weight category. This technique is particularly useful when the yarn label is missing or if you’re using hand-spun or unlabelled yarn. Knowing the WPI helps you substitute yarns accurately, ensuring that your gauge and the overall appearance of your project remain consistent with the pattern’s specifications.
How to Measure WPI
Measuring WPI is a straightforward process:
Take a ruler or a WPI tool and hold it horizontally.
Wrap the yarn around the ruler without overlapping, but snugly enough that there are no gaps between wraps.
Count the number of wraps that fit within one inch.
Use a WPI chart to match the number of wraps to a specific yarn weight category.
For example, if you count 21 wraps in one inch, you have a fingering weight yarn. This method provides a quick and reliable way to identify yarn weights, especially for unlabelled stash yarns or hand-spun yarns.
Yarn Weight Table with WPI
Yarn Weight | Yarn Weight | Usual Ply | WPI | Recommended Hook Size |
 | Lace Fingering Thread | 1 - 3 ply | 30 - 40+ WPI | 1.4 - 2.25mm |
 | Sock Fingering Baby | 4 ply | 14 - 30 WPI | 2.25 - 3.5 mm |
 | Sport Baby | 5 ply | 12 - 18 WPI | 3.5 - 4.5 mm |
 | DK Light Worsted | 8 ply | 11 - 15 WPI | 4.5 - 5.5 mm |
 | Worsted Aran Afghan | 10 - 12 ply | 9 - 12 WPI | 5.5 - 6.5 mm |
 | Bulky Chunky Craft Rug | 12 - 14 ply | 6 - 9 WPI | 6.5 - 9 mm |
 | Super bulky Super chunky Roving | 14 - 16 ply | 5 - 6 WPI | 9 - 15 mm |
 | Jumbo Roving | 16+ ply | 1 - 4 WPI | 15+ mm |
Conclusion
Understanding WPI and yarn weights is fundamental for achieving the best results in your crochet projects. By learning how to measure WPI and choosing the right yarn weight, you ensure that your creations have the correct gauge, drape, and overall look. Whether you’re following a pattern or designing your own, these skills will help you select the perfect yarn for any project. Happy crocheting!
